碳纤维增强陶瓷基复合材料抗氧化涂层研究进展

对碳纤维增强陶瓷材料抗氧化涂层的要求、组成与制备工艺以及最近抗氧化涂层体系的发展做了综述。并且对今后抗氧化涂层的发展作了一些展望。     

多线程控制技术在面向对象实时仿真中的应用

随着实时仿真复杂性的提高,单个的处理器不足以完成所有的必需仿真计算任务。希望能在不同的处理器上完成实时仿真的不同任务,对称多处理器的机制需要软件支持,以使每个处理器通过共享内存进行信息交换。利用多线程控制技术,可以在非全进程开销或不使用共享内存的条件下,使用多处理器。其理由在于线程本身就蕴涵有共享地址的概念。一个多线程的实时程序,利用其中的主线程控制其它的辅助线程,每个处理器用于完成一个辅助的实时计算线程,主线程负责实时时钟的监控,当时钟到达时,启动相应的辅助线程,辅助线程利用图形用户界面(GUI)来监控仿真的进行。     

铝粉颗粒燃烧产物的平均弥散度计算研究

采用金属颗粒的扩散燃烧模型和燃烧产物的均匀多相成核理论，对铝粉燃烧所形成的Al2O3平均弥散度进行了计算研究。根据计算结果，对铝粉燃烧区域中的温度、燃烧产物的过饱和度及其凝聚成核速率的变化规律进行了分析讨论。并研究了环境因素对上述多数和铝粉燃烧产物平均弥散度的影响。     

基于欧拉方程的跨声速翼型设计

给出了一种基于欧拉方程的跨声速翼型设计方法。方法以Ｔａｋａｎａｓｈｉ提出的“正反迭代余量修正”设计原理为基础，在气动力分析模块中，以欧拉方程为基本控制方程，并采用Ｗａｌｚ边界层方法对其进行粘性修正；反设计模块采用经过改进的二维翼型设计方法。方法的程序经过几个设计实例主题证明是有效而实用的。     

Recursive mode star identification algorithms

Star identification can be accomplished by several different available algorithms that identify the stars observed by a star tracker. However, efficiency and reliability remain key issues and the availability of new active pixel cameras requires new approaches. Two novel algorithms for recursive mode star identification are presented here. The first approach is derived by the spherical polygon search (SP-search) algorithm, it was used to access all the cataloged stars observed by the sensor field-of-view (FOV) and recursively add/remove candidate cataloged stars according to the predicted image motion induced by camera attitude dynamics. Star identification is then accomplished by a star pattern matching technique which identifies the observed stars in the reference catalog. The second method uses star neighborhood information and a catalog neighborhood pointer matrix to access the star catalog. In the recursive star identification process, and under the assumption of "slow" attitude dynamics, only the stars in the neighborhood of previously identified stars are considered for star identification in the succeeding frames. Numerical tests are performed to validate the absolute and relative efficiency of the proposed methods.     

真实气体流动的相似规律

本文从具有化学反应的NS方程出发导出了真实气体流动的相似律,分别给出了高温空气非平衡流、平衡流和冻结流的相似参数。文中还讨论了航天飞机轨道器各种Mach数范围内的真实气体流动的相似参数和实验模拟问题。     

Eruptive prominences as sources of magnetic clouds in the solar wind

Large amounts of coronal material are propelled outward into interplanetary space by Coronal Mass Ejections (CMEs). Thus one might expect to find evidence for expanding flux ropes in the solar wind as well. To prove this assumption magnetic clouds were analyzed and correlated with H-observations of disappearing filaments. When clouds were found to be directly associated with a disappearing filament, the magnetic structure of the cloud was compared with that of the associated filament. Additionally the expansion of magnetic clouds was examined over a wide range of the heliosphere and compared with the expansion observed for erupting prominences.     

含非对称裂纹三维有限大体应力强度因子能量释放率方法的封闭解

 本文提出一种新的半工程半解析的方法,导出含非对称裂纹三维有限大体应力强度因子的封闭解。根据此方法,只需少量的机时,即可获得一系列结果。本方法及所得结果在工程上有实际应用价值。     

500 – 3200 Å observations of the interacting binary stars V356 Sgr and β Lyr

In this paper we present new results from the Voyager ultraviolet spectrometers and the IUE spacecraft on V356 Sgr and β Lyr. The V356 Sgr observations cover, in detail, two eclipses and include one IUE high dispersion SWP image. During both eclipses the total strength of the UV emission lines were found to be invariant. Also, an uneclipsed UV continuum was detected at wavelengths shorter than 1600 Å. The IUE high dispersion SWP spectrum revealed that the emission lines are extremely broad, almost symmetrical lines with weak, slightly blue shifted absorption components. No evidence of carbon is seen in the emission or absorption spectrum of V356 Sgr in eclipse. A model for the origin of the circumstellar matter in this binary system is presented. The Voyager ultraviolet observations of β Lyr show a strong far-UV continuum that is detectable down to 912 Å The far-UV continuum flux level was variable on time scales shorter than the orbital period and displayed no obvious orbital modulation or eclipses. The spectral shape of the far-UV continuum closely resembles that of a UX UMa type cataclysmic variable. On 16 August 1985 an rapid brightening of the far-UV continuum was observed which was also reminiscent of cataclysmic variables. Analysis of the β Lyr data suggest that the central object must be small, with a radius on the order of 1 R_⊙ or less.